Getting gSender and Lightburn to play together

gSender ❓ Question
1

LongMill Mk1 running an SLB
gSender version 4.1.2
Lightburn 2.0.5

I have not used LB for quite a while so I don’t know exactly when this started.

I created a test toolpath in LB. LB would jog the LM, but the laser would not fire at all. I thought that it might be a wiring issue, so I created a test toolpath in VCarve, and wrote out the gcode to gSender. I ran the test in gSender and it ran fine. So, wiring was not the issue.
Through some playing around, I found the solution. gSender must be in laser mode when it is closed before opening LB. gSender is not connected to the SLB as this point, but it appears that the SLB retains the last spindle/laser setting. If gSender is closed in spindle mode, LB will not fire the laser.
Is this a grblHal issue or a function of gSender? If the latter, is there a firmware setting that needs to be changed to allow gSender to “release” the setting so that LB can control the laser?

2

I’m not so certain on the Lightburn side of things but can illuminate how toggling between spindle/laser mode in gSender works.

Toggling on laser mode in gSender:

  • Applies offset code on grbl, does not apply offset code on grblHAL because it’s handled in the firmware with dedicated EEPROM settings ($740, $741)
  • Applies updates spindle min/max with configured laser values on grbl, does not apply laser min/max on grblHAL because it’s handled by the firmware with dedicated EEPROM settings ($730, $731)
  • Applies laser mode ($32=1).

I think the last point is the relevant one for you and the one change that might impact you.

Either in gSender (or Lightburn, if they have a way to directly type commands to the controller - I actually can’t answer that unfortunately) try the following:

  1. Make sure you’re in spindle mode (so the laser shouldn’t work)
  2. In the console, type $32=1
  3. Disconnect in gSender, try to run file in Lightburn.
  4. It should work with laser mode enabled ($32=1)
3

@KGN Tks much, Kevin. I can confirm that in LB $32=1 is set. That was the first thing that I thought of. It doesn’t matter. If gSender was closed in spindle mode, LB will not fire the laser at all. It won’t even fire the test.
This is not a big deal. It’s a simple matter to open gSender, set it to laser mode, then shut it down. LB will then behave. I simply wondered if there was a setting in gSender that I was missing.